In recent years, there has been significant investment in the industry in the area of automotive vehicle maintenance operations. This investment has been heavy in shop or facility or service center optimization for increasing the efficiency of the technician/worker as well as their effectiveness and safety. From shop design and scheduling systems to integration of handheld devices for personal display of vehicles diagnostics, investments in Lean Operations are paying off in terms of human capital efficiency, volume, and margin. Fleet managers frequently measure service center efficiency in terms of percentage of labor hours billed, and number of jobs completed/vehicle turnover. Service providers operate under the assumption that improving these metrics increases service center profitability.
Automotive technicians spend approximately fifteen to twenty minutes per service order, or approximately seventy-five minutes per day when servicing five vehicles, on the following routine exercises: retrieving the vehicle from the service center parking lot, driving it to the service bay equipped with a suitable vehicle lift, aligning it to the vehicle lift, manually positioning the lift to the vehicle lifting points to ensure a secure and safe hoist, disengaging the lift from the vehicle, and subsequently returning the vehicle to the service center parking lot once the service has been completed. This time typically depends on service center setup, vehicle type and vehicle lift type.
As a general rule, it is required to raise a vehicle above ground in order to perform various services, such as inspection, repair or other maintenance on the vehicle. For this purpose, various types of lifts have been devised in the industry. The lifts of particular relevance for the present disclosure are lifts that require a non-trivial amount of human/technician expertise and/or time for properly aligning and engaging them with the vehicle being serviced. Such lifts may be frame-engaging or wheel-engaging, they may be mobile or fixed lifts, and they may be drive-on or in-ground type.
A mobile column lift is a lift in which a manually moveable column or vertical lift is used at each axled wheel of an automotive vehicle. As such, these are by design wheel-engaging lifts, but with appropriate frame adapters, such as bumper-adapters, they can be converted into frame-engaging lifts as well. The column lifts are coordinated by a control system that supervises the lifting and lowering of the vehicle in a controlled, safe and stable manner. A representative prior art mobile column or vertical lift 100 is depicted in FIG. 1A. FIG. 1A shows a left isometric view of a column/vertical lift 100 having a carriage assembly 102. Carriage assembly 102 of lift 100 has an engagement mechanism 104 for engaging an axled wheel of a vehicle.
The lift also has two resting arms 112A and 112B that rest on the ground as carriage assembly 102 with its engagement mechanism 104 lifts an axled wheel of a vehicle. There is also a hand-truck or dolly or tie-bar mechanism 106 with its handle 108 using which a technician can manually transport lift 100 on three wheels 110A, 110B and 110C to a desired engagement location. The engagement location is in a service bay of a service shop/facility where the vehicle is being serviced.
FIG. 1B shows lift 100 in its raised position. In this position, engagement mechanism 104 is engaged with an axled wheel 120 of a vehicle being serviced. FIG. 1B also shows axle 122 of wheel 120 while the rest of the vehicle is omitted from the drawing to avoid detraction. Note that FIG. 1B shows the vehicle being serviced raised above ground so a technician or service/repair person can view the underside of the vehicle. In this position, resting arms 112A and 112B firmly rest on the ground for stably supporting/compensating the weight of the vehicle that is in turn being held in the raised position by carriage assembly 102 and its corresponding engagement mechanism 104.
Obviously, FIG. 1A-B show one column/vertical lift 100 of a system of presumably several lifts. One mobile column/lift such as lift 100 is used to raise each axled wheel of the vehicle being serviced. The rest of the mechanical or electrical componentry of the lift, including any lifting gears, hydraulics, motors, etc. are well known to those skilled in the art, and are not explicitly shown in FIG. 1A-B.
There are many different techniques in the prior art that describe the use of such mobile column lifts. Lift manufacturers have continually developed and integrated technology into their products to increase the percentage of labor hours billed and the vehicle turnover per lift or bay per day. For example, Rotary Lift has released its remote-control product Rotary MCH19 FLEX Mobile Lifting System to control mobile column lifting and lowering from a distance. Also Rotary Shockwave increases the lifting speed to increase productivity, which the Rotary Lift Shockwave ROI Calculator claims can increase vehicle turnover by one vehicle per week per lift, simply by cutting approximately thirty seconds off lifting time.
U.S. Patent Publication No. 2011/0097187 A1 to Kelley et al. discloses a mobile column lift system comprising a column lift and one or more laser modules. The lift includes one or more lifting members that are operable to selectively raise and lower a vehicle. The laser modules are operable to emit at least one laser beam to provide a visual indicator on a vehicle positioned relative to the one or more lifting members. The visual indicator may include a line, crosshairs, target, dot, including combinations and patterns. The visual indicator may flash or remain solid. The visual indicator may be any color. One or more sensors may provide activation and/or de-activation of the laser modules in response to sensing the presence of a vehicle. An operator may view the visual indicator on the vehicle to confirm proper positioning of the vehicle relative to the lifting members.
U.S. Pat. No. 8,083,034 B2 to Bordwell et al. teaches a lift control interface operable to control and monitor a mobile column lift system for its vertical lifting/lowering operations. Each column lift in the system has such a lift control interface. The lift control interface allows a user to assign column lifts to a lift system. One or more of the assigned lifts may be assigned to a column control group. The user may lock the selection of these columns. The status of the assigned, selected, and locked lift columns may appear on every lift control interface in the lift system. The user may govern operation of the selected columns in the column control group from a single control interface, such as any control interface at any of the selected lifts. The lift control may include visual representations showing the relationships between the column lifts and a vehicle, such as with lift column icons being positioned around a vehicle icon.
U.S. Pat. No. 8,567,761 B2 to Jong et al. discloses a system and method for lifting and lowering an object such as a vehicle. It uses at least two mobile column lifts, communication means for communication with the two column lifts and a position-determining means for carrying out a position determination for each of the two column lifts. It also has a selection means for selecting at least one of the column lifts on the basis of the position determination. It further has a control unit co-acting with the communication means during use for the purpose of controlling the column lifts selected with the selection means.
U.S. Pat. No. 6,634,461 B1 to Baker teaches a mobile column lift system that coordinates the raising and lowering of a vehicle relative to a surface by using wireless communications. The lift system includes at least two lift mechanisms each having a post, a carriage, an actuating device and a control device. The carriage is slidably coupled to the post and is adapted to support a portion of the vehicle. The actuating device is coupled with the carriage and is capable of moving the carriage relative to the post. The control device is coupled with the actuating device and is capable of communicating by wireless signals with the other control device. The control devices communicate by wireless signals to coordinate the movement of the carriages relative to the posts to raise or lower the vehicle. Further, a rechargeable battery can provide power to the control device to allow for increased mobility of the lift system.
U.S. Patent Publication No. 2014/0324214 A1 to Elliott teaches a lift control system and method including a plurality of mobile column lifts with a lift unit having a lift mechanism configured to respond to a motion command. It also includes a lift processor configured to determine a lift speed value, and a lift transceiver configured to transmit the lift speed value. The lift control system further includes a central control unit having a central transceiver configured to receive the lift speed value from the lift control unit. The central processor is configured to determine a communicated speed value in response to the lift speed value. The lift transceiver is operable to receive the communicated speed value and the lift processor is operable to modify a lift operating speed of the lift mechanism in response to the communicated speed value and the motion command.
After a brief review of mobile column lifts of the prior art, let us now review fixed vehicle lifts. A fixed lift obviously stays attached to the service bay where it is installed in a service center or shop or facility. A typical configuration, called a fixed column lift is a lift that has arms to engage an automotive vehicle. Typically, the arms are swing-arms that extend underneath the vehicle. These lifts are typically frame-engaging lifts, but with appropriate wheel adapters, they can be turned into wheel-engaging lifts as well.
FIG. 1C shows a two-post fixed lift system 150 consisting of a fixed lift, column or post 152A and another fixed lift, column or post 152B. Lift 150 has carriage assemblies 154A and 154B that move up and down in columns 152A and 152B respectively powered by the motors shown. Note that in the left isometric view of lift 150 shown in FIG. 1C, only carriage assembly 154B is visible. The lift engages with a vehicle using swing-arms 156A, 156B attached to carriage assembly 154A, and swing-arms 156C, 156D attached to carriage assembly 154B. Note that swing-arm 156B is not visible in the view shown in FIG. 1C but is presumed to exist.
Swings arms 156A-D are also telescopic and can extend inward or outward as shown. Further, swing-arms 156A-D can swing or rotate or pivot about their axes. At the end of each swing-arm of fixed lift 150, there is a lift pad or support plate, which eventually makes contact with a lifting point of the vehicle during its lifting/lowering. Specifically, there is a lift pad 158A at the end of swing-arm 156A, lift pad 158B at the end of swing-arm 156B, and so on. Similarly to the mobile column lifts, there are many prior art references that discuss such a fixed two-post or twin lift configuration with swing-arms.
U.S. Pat. No. 9,376,296 B2 to Nussbaum teaches a fixed two-post hoist/lift with two lifting columns arranged at both sides of a vehicle. Each lift has two support arms that are supported in a horizontally pivotal and longitudinally adjustable fashion at the lifting column, and each having at their free end a support plate. The support plates are position-able at support positions underneath a vehicle as specified by the vehicle manufacturer by an appropriate movement of the support arm. The manufacturer support positions are saved as target positions according to corresponding vehicle model in a data memory of the hoist.
The system allows for a semi-automatic or automatic operation by employing a camera affixed in the service bay above the vehicle for optically detecting the contour of the vehicle in reference to the hoist. The coordinates of actual positions of the support plates of the hoist are determined by measurements and perhaps calculations. A computer makes a comparison between the target and actual coordinates, and enables a lifting process of the support arms only when differences between the target and the actual coordinates are within a predetermined tolerance.
U.S. Pat. No. 6,279,685 B1 to Kogan et al. teaches a twin post lift system with a master and slave cylinder. The master and slave cylinders each drive a lifting carriage, and each of the lifting carriages is mounted within, and is restricted to longitudinal travel within an upright/vertical member. In the event that there is a loss of pressure in the hydraulic system under load, it is important that the lift be prevented from descending unexpectedly, or uncontrolledly. The upright member can be manufactured in the form of a roll formed channel section.
The legs of the channel section are formed to define guides for guide followers mounted on the lifting carriage, thereby restraining the travel of the lifting carriages to travel in the vertical direction. The lifting carriage has a rack formed on its back face. The rack is nested within the upright member and is not visible in use. The back of the channel is formed with an outwardly protruding step to accommodate the rack. A safety stop, in the nature of a spring-loaded safety dog, is mounted to the upright member and extends through the wall of the protrusion to engage the rack.
U.S. Pat. No. 5,954,160 to Wells et al. discusses a wheel engaging vehicle lift for raising a vehicle relative to the ground and for supporting the vehicle in a raised position. It includes first and second support columns standing vertically upward from the ground. A first carriage is movably attached to the first support column and a second carriage is movably attached to the second support column. A first pair of arms extend away from the first carriage and a second pair of arms extend away from the second carriage. The first and second pairs of arms are each rotatable about a substantially vertical axis proximate to a first end of the arms. A wheel engaging adapter is removably secured proximate to an opposite end of the first and second pairs of arms. The adapters are each rotatable about a substantially vertical axis proximate to the second end. The structure enables a conventional two-post frame-engaging lift to be converted into a two-post wheel-engaging vehicle lift, and vice versa.
It is easily observed that the prior art only teaches systems of lifts where a technician is required for the proper positioning of the lift underneath the vehicle. The technician may perform this operation either completely manually or with some optical aid. In the case of mobile column lifts, the technician is also required to transport the column lift, such as lift 100 of FIG. 1A-B to its engagement location. This is accomplished by the technician by using a hand-truck/dolly/tie-bar mechanism 106, handle 108 and wheels 110A-C as shown in FIG. 1-B. In the case of two-post fixed lifts, the technician is required to position arms 156A-D and lift pads 158A-D of lift 150 of FIG. 1C underneath the lifting points of the vehicle for safe hoisting.
Thus, a key limitation of the prior art is that it fails to disclose vehicle lifts whose operation can be fully automated. In the case of mobile column lifts, this automation may involve motorization of the transport mechanism of mobile column lifts so that they are self-propelled or self-guided. In the case of both fixed and mobile column lifts, this automation may further involve motorization/automation of their engagement mechanism to engage with the vehicle.
Explained further, there are no teachings in the prior art that would enable mobile column lifts to automatically transport to and engage with an automotive vehicle without requiring a technician or requiring only a minimal assistance of a human technician. Similarly, there are no prior art teachings that provide for automating the engagement of fixed column lifts for properly positioning the swing-arms underneath the vehicle without requiring technician assistance.
There are also no teachings in the traditional art that will enable an autonomous vehicle to automatically drive itself to a service bay with a suitable lift in a service center when a service of the vehicle is due. The prior art also does not teach any techniques where sensors present onboard the vehicles (autonomous or otherwise) are used to assist in the above mentioned automatic transportation and/or engagement of the lifts. The prior art also does not effectively utilize sensors deployed on the lifts themselves and/or the environment for the above mentioned automation.
An advantage of such a system will be reduced technician time and labor costs, thereby positively influencing the economics of the system and the bottom-line of the service center. That is because, currently vehicle retrieval and engagement process takes a significant percentage of the overall technician time required in a service order. Further, according to industry leaders, ninety percent of accidents are related to human errors, and technicians face both incidental and chronic injuries due to workplace conditions.
Thus, such a system would also have the advantage of increasing worker safety because the majority of vehicle lift accidents occur as a result of human error during engaging the vehicle lift with the vehicle. The improvement in worker safety would lead to a reduction in missed work days due to an improvement in technician workplace ergonomics, as well as avoidance of missed days due to injuries. This will also lead to a reduction in insurance expenses for the service center. Additionally, such a system absent from the prior art, would also minimize potential damage to the vehicle by incorrect positioning of the lifts by human technicians.